-- | Hedgehog generators for the messages
module Generator
  ( abilityGen
  , abilityV1Gen
  , hintGen
  , connectionHintGen
  , ackGen
  , transitMsgGen
  , transitAckGen
  , nonceBytesGen
  , purposeGen
  )
where

import Protolude

import Hedgehog (MonadGen(..))
import qualified Crypto.Saltine.Class as Saltine
import qualified Crypto.Saltine.Core.SecretBox as SecretBox
import Crypto.Saltine.Internal.ByteSizes (boxNonce)
import qualified Hedgehog.Gen as Gen
import qualified Hedgehog.Range as Range

import Transit.Internal.Messages
  ( Ability(..)
  , AbilityV1(..)
  , Hint(..)
  , ConnectionHint(..)
  , Ack(..)
  , TransitMsg(..)
  , TransitAck(..)
  )
import qualified Transit.Internal.Crypto as C

abilityGen :: MonadGen m => m Ability
abilityGen = Ability <$> abilityV1Gen

abilityV1Gen :: MonadGen m => m AbilityV1
abilityV1Gen = Gen.choice
  [ pure DirectTcpV1
  , pure RelayV1
  ]

hintGen :: MonadGen m => m Hint
hintGen = Hint <$> abilityV1Gen
           <*> Gen.double (Range.linearFrac 0.0 5.0)
           <*> Gen.text (Range.linear 0 100) Gen.unicode
           <*> Gen.word16 (Range.linear 0 maxBound)

connectionHintGen :: MonadGen m => m ConnectionHint
connectionHintGen = Gen.choice
  [ Direct <$> hintGen
  , Relay <$> abilityV1Gen <*> Gen.list (Range.linear 0 10) hintGen
  ]

ackGen :: MonadGen m => m Ack
ackGen = Gen.choice
  [ FileAck <$> Gen.text (Range.linear 0 100) Gen.ascii
  , MessageAck <$> Gen.text (Range.linear 0 100) Gen.ascii
  ]

transitMsgGen :: MonadGen m => m TransitMsg
transitMsgGen = Gen.choice
  [ Error <$> Gen.text (Range.linear 0 100) Gen.unicode
  , Answer <$> ackGen
  , Transit
    <$> Gen.list (Range.linear 0 5) abilityGen
    <*> Gen.set (Range.linear 0 5) connectionHintGen
  ]

transitAckGen :: MonadGen m => m TransitAck
transitAckGen = TransitAck
  <$> Gen.text (Range.linear 0 5) Gen.unicode
  <*> Gen.text (Range.singleton 64) Gen.hexit

nonceBytesGen :: MonadGen m => m ByteString
nonceBytesGen = Gen.bytes (Range.singleton boxNonce)

purposeGen :: MonadGen m => m C.Purpose
purposeGen = Gen.choice [ pure C.SenderHandshake
                        , pure C.ReceiverHandshake
                        , pure C.SenderRecord
                        , pure C.ReceiverRecord
                        , pure C.RelayHandshake ]